A recent whole-genome duplication divides populations of a globally-distributed microsporidian

The Microsporidia are a major group of intracellular fungi and important parasites of animals including insects, fish, and immunocompromised humans. Microsporidian genomes have undergone extreme reductive evolution but there are major differences in genome size and structure within the group: some are prokaryote-like in size and organisation (<3 Mb of gene-dense sequence) while others have more typically eukaryotic genome architectures. To gain fine-scale, population-level insight into the evolutionary dynamics of these tiny eukaryotic genomes, we performed the broadest microsporidian population genomic study to date, sequencing geographically isolated strains of Spraguea, a marine microsporidian infecting goosefish worldwide. Our analysis revealed that population structure across the Atlantic Ocean is associated with a conserved difference in ploidy, with American and Canadian isolates sharing an ancestral whole genome duplication that was followed by widespread pseudogenisation and sorting-out of paralogue pairs. While past analyses have suggested de novo gene formation of microsporidian-specific genes, we found evidence for the origin of new genes from noncoding sequence since the divergence of these populations. Some of these genes experience selective constraint, suggesting the evolution of new functions and local host adaptation. Combining our data with published microsporidian genomes, we show that nucleotide composition across the phylum is shaped by a mutational bias favoring A and T nucleotides, which is opposed by an evolutionary force favoring an increase in genomic GC content. This study reveals ongoing dramatic reorganization of genome structure and the evolution of new gene functions in modern microsporidians despite extensive genomic streamlining in their common ancestor

Legal aid in Iceland

The aim of the chapter is to give a brief overview of the development of legal aid in civil cases in Iceland. The current law, which came into force in 1992, allows for legal aid to be granted not only on the basis of low economic status, but also if the outcome of the case is deemed to have great public or individual significance. The latter criterion, however, remains contested, seemingly as a matter of right-wing vs. left-wing politics. The discussion on legal aid has, however, mostly been framed in narrow legalistic terms in response to suggestions to cut state costs. It is therefore difficult to discern whether and to what extent legal aid in Iceland is conceptualised as a charity, right, or individual responsibility